It's pretty simple - communism is "real communism" when it works, and it's not when it doesn't. It's similar to how it's not "real capitalism" when things go wrong in a capitalist system.
Are there examples where communism did not turn into authoritarian?
Cuba isn't doing too badly even though it's authoritarian. It's no soviet union, DDR or North Korea. The biggest problems they have are due to US sanctions.
But I think extremes never work. Neither strict communism nor all-out capitalism.
Is that pertinent to whether or not China is currently communist in anything but name only? No.
I'm genuinely curious because all we hear about are the bad examples
I’ve been wondering the same but maybe we only have these examples because the only successful attempts to forcefully take power away from the capitalists has been by authoritarians.